1. Field of the Invention
The present invention relates to a microwave plasma processing method and apparatus. More particularly, it relates to a microwave plasma processing method and apparatus which are well suited to subject samples, such as semiconductor device substrates, to an etching process, a film forming process, etc. by the use of a microwave plasma processor of the type wherein a waveguide section includes electric discharge means isolated from a waveguide for the propagation of microwaves and having a plasma generation region therein.
2. Description of the Prior Art
As microwave plasma processing techniques in the prior art, there have been known examples as disclosed in "HITACHI REVIEW", Vol. 71, No. 5, pp. 33-38 (1989) and Japanese Patent Publication No. 34461/1978, wherein an electric discharge tube made of quartz is disposed inside a waveguide for propagating microwaves, plasma is generated within the electric discharge tube by the synergy of a microwave electric field and a magnetic field, and a semiconductor wafer set in a processing chamber is subjected to an etching process by utilizing the plasma.
Also, there have been known examples as disclosed in Japanese Patent Laid-open Nos. 103340/1984 and 25420/1989, wherein an electric discharge tube made of quartz is disposed inside a circular waveguide for propagating microwaves, plasma is generated within the electric discharge tube under the action of a microwave electric field and a magnetic field, and a sample, such as semiconductor device substrate, set in a processing chamber is subjected to an etching process or a film forming process by utilizing the plasma.